Interference reduction

Abstract

A method of reducing inter cell interference in a wireless communication network, a network control node, network access node, user equipment and computer program product operable to implement that method. The method is for use in a network comprising a plurality of network access nodes, each supporting a region of radio overage, and the method comprises: discovering, for a first network access node, at least one adjacent network access node; allocating at least one predetermined shared radio channel for radio communication commenced within an overlapping radio coverage region between said first network access node and said adjacent network access node; and communicating an indication of said at least one predetermined shared radio channel to said first network access node and said adjacent network access node. The method enables shared radio channels to be used in a “soft handover” type scenario, by enabling adjacent network access nodes to decipher and decode transmissions made by user equipment operating in overlap regions in a network. Such methods may be particularly suited to user equipment operating in a Cell_FACH mode.

The invention claimed is: 
     
       1. A network control node method of reducing inter cell interference in a wireless communication network comprising a plurality of network access nodes supporting a region of radio coverage, said method comprising:
 discovering, for a first network access node, at least one adjacent network access node; 
 allocating, by the network control node, at least one predetermined shared radio channel for which user equipment must compete for radio communication commenced within an overlapping radio coverage region between said first network access node and said at least one adjacent network access node; and 
 communicating an indication of said at least one predetermined shared radio channel to said first network access node and said adjacent network access node, wherein said method further comprises: 
 determining a first at least one predetermined shared radio channel for radio communication commenced within an overlapping radio coverage region between said first network access node and said adjacent network access node when said first network access node supports a serving cell and said at least one adjacent network access node supports a potential target cell; 
 determining a second at least one predetermined shared radio channel for radio communication commenced within an overlapping radio coverage region between said first network access node and said at least one adjacent network access node when said first network access node supports a potential target cell and said at least one adjacent network access node supports a serving cell. 
 
     
     
       2. The method according to  claim 1 , comprising allocating a sub-set of all available shared radio channels to said allocated at least one predetermined shared radio channel for radio communication commenced within an overlapping radio coverage region between said first network access node and said adjacent network access node. 
     
     
       3. The method according to  claim 1 , comprising:
 determining a pair of said first at least one predetermined shared radio channel and said second at least one predetermined shared radio channel for a pair of said first network access node supporting a serving cell and said at least one adjacent network access node supporting a potential target cell. 
 
     
     
       4. The method according to  claim 1 , wherein said communicating an indication of said at least one predetermined shared radio channel to said first network access node and said adjacent network access node comprises an indication of how to decode communications made on said at least one predetermined shared radio channel. 
     
     
       5. A non-transitory computer-usable data carrier storing instructions that, when executed by a computer, cause the computer to perform the method of  claim 1 . 
     
     
       6. A network control node operable to reduce inter cell interference in a wireless communication network comprising a plurality of network access nodes, supporting a region of radio coverage, said network control node comprising:
 discovery logic, operable to discover, for a first network access node, at least one adjacent network access node; 
 allocation logic, operable to allocate, by the network control node, at least one predetermined shared radio channel for which user equipment must compete for radio communication commenced within an overlapping radio coverage region between said first network access node and said adjacent network access node; and 
 communication logic, operable to communicate an indication of said at least one predetermined shared radio channel to said first network access node and said adjacent network access node, wherein said network control node further comprises: 
 determination logic, operable to determine a first at least one predetermined shared radio channel for radio communication commenced within an overlapping radio coverage region between said first network access node and said adjacent network access node when said first network access node supports a serving cell and said at least one adjacent network access node supports a potential target cell and to determine a second at least one predetermined shared radio channel for radio communication commenced within an overlapping radio coverage region between said first network access node and said at least one adjacent network access node when said first network access node supports a potential target cell and said at least one adjacent network access node supports a serving cell. 
 
     
     
       7. A network control access node method of controlling inter cell interference in a wireless communication network comprising a plurality of network access nodes supporting a region of radio coverage, said method comprising:
 a network access node determining at least one predetermined shared radio channel for which user equipment must compete for radio communication commenced within an overlapping radio coverage region; 
 preparing for communications within said communication network on said predetermined shared radio channel by allocating said at least one predetermined shared radio channel to a request for a shared radio channel originating within said overlapping radio coverage region, wherein said request comprises a request for at least one predetermined shared radio channel for radio communication and said method further comprises determining whether said requested at least one predetermined shared radio channel for radio communication is available for use and, if not, allocating another of said at least one predetermined shared radio channels. 
 
     
     
       8. The method of controlling inter cell interference according to  claim 7 , wherein said preparing comprises:
 preparing to decode information transmitted on said predetermined shared radio channel. 
 
     
     
       9. A non-transitory computer-usable data carrier storing instructions that, when executed by a computer, cause the computer to perform the method of  claim 7 . 
     
     
       10. A network access node operable to control inter cell interference in a wireless communication network comprising a plurality of network access nodes supporting a region of radio coverage, said network access node comprising:
 determination logic, operable to determine at least one predetermined shared radio channel for which user equipment must compete for radio communication commenced within an overlapping radio coverage region; 
 preparation logic, operable to prepare for communications within said communication network on said predetermined shared radio channel by allocating said at least one predetermined shared radio channel to a request for a shared radio channel originating within said overlapping radio coverage region, wherein said request comprises a request for at least one predetermined shared radio channel for radio communication and said network access mode further comprises determination logic, operable to determine whether said requested at least one predetermined shared radio channel for radio communication is available for use and, if not, allocate another of said at least one predetermined shared radio channels.